All generalizations are false, including this one.
-Mark Twain
Why is it called Park’s, not Blondel’s, Transformation?
The History of the DQ Transformation
Park’s transformation can be considered to be the single theoretical contribution that triggered the development of advanced design, control, and analysis of electrical machines (motors and generators). To most practicing engineers and researchers in this field, the story goes like this:
After Nikola Tesla invented the AC machine in the 1880s, it took the electrical engineers over 3 decades of struggling with AC circuits analysis before Robert H. Park (1902–1994) published his seminal paper, in 1929, “Two Reaction Theory of Synchronous Machines”. In that paper, the brilliant young engineer solved the problem mathemagically by introducing the dq0-transformation that has been called after him, the Park’s transformation, which transforms the natural 3-phase AC reference frame into a fictitious 2-circuit rotating reference frame.
The Park’s transformation is a brilliant idea indeed, except that it was not invented by Park… Have you ever heard of André-Eugène Blondel (1863–1938)? Here is the complete story.
Continue reading “Why is it called Park’s, not Blondel’s, Transformation?”Electric Motors Should be More Fun
We encounter mechanical phenomena all the time. We see things move, fall, spin, oscillate, break, etc. Electrical phenomena, on the other hand, are not always visible. Therefore, it has become a common practice to use mechanical analogies to explain and teach less visible concepts.
We compare electrons to water when explaining voltage, current, and Ohm’s law. The inductor is often compared to a spring, and the capacitor to a mass/inertia. The electrical resonance can then be compared to the mechanical resonance.
Even control engineers use mechanical analogies to illustrate their concepts; the proportional-derivative controller is nothing but a mass-damper system in that sense.
The theory of AC motors involves many difficult concepts, often explained with mathematical formulas and graphs. This is an obstacle to effective teaching and vulgarization. In this post, I propose 3 ideas to make the teaching of AC motors more fun. My goal is to stimulate more ideas and analogies; if you have some, please share them.
Continue reading “Electric Motors Should be More Fun”Between Waterfall and Agile – The Grey Area
What is the development theory that Steve Jobs used to develop the Apple II computer? Do you think that when Thomas Edison invented and mass-produced the light bulb, and many other inventions, he was thinking about what project development model to apply? What model was on the mind of Henry Ford when he revolutionized the automotive industry (besides the model T)?
If you have great visionary leaders who have a good understanding of the market, and talented people who master the state-of-the-art technology, with a bit of luck, you can develop a best-in-class product, and disrupt the market, without the need for any management/development theory. Following your success, people (not as smart as your people) will try to extract lessons from your good practices, theorize them, and sell them to other companies as remedies to their problems. Good practices will always help to improve the outcome, but will never fix the problem of narrow-minded leadership and unmotivated people.
This sets the ground for the sequel.
Product/Software Development
The development of a product/software comprises the following key activities:
Continue reading “Between Waterfall and Agile – The Grey Area”Success !
The Great Influenza – John Barry
Title: The Great Influenza: The Story of the Deadliest Plague in History
Author: John M. Barry
Publication Date: 2004
Recommendation Score: 4.5/5
The H1N1 influenza A virus was called the Spanish flu. This is mainly because the Spanish press was reporting about it freely, in contrast to the censored press in the countries involved in world war I. This flu is arguably the deadliest pandemic in history. It happened between 1917 and 1920 with a peak in 1918. The war helped the virus spread by both displacing men between countries, and by censorship that minimized the death reports to maintain morale. The book describes this period in great detail.
When I was reading this book, I heard a president of a European country comforting his people by claiming that the COVID-19 crisis and its context (economic crisis, terrorism) is the worst in modern history. Political dogma aside, we are far better, with our modern technology, than the generation that endured the flu pandemic and WWI. We should expect the worst.
The book was written over 15 years ago. The author, John Barry, warns against the risk of flu pandemic outbreaks that may occur any time. He points out the fragility of the just-in-time supply chain, and the over-optimization of the industries, including the health industry, which makes us poorly prepared in case of a pandemic.
Loonshots – Safi Bahcall
Title: Loonshots: How to Nurture the Crazy Ideas That Win Wars, Cure Diseases, and Transform Industries
Author: Safi Bahcall
Publication Date: 2019
Recommendation Score: 4.5/5
Safi Bahcall is an entrepreneur with a Ph.D. in physics. In his book “Loonshots” he tries to apply the principle of physics to innovation in business ventures. The book is inspired by two success stories in recent American history 1) the turnaround of the Bell Telephone Company, led by Theodore Vail, during the first decade of the 20th century which resulted in creating the Bell Labs, 2) and by the efforts of Vannevar Bush to improve the technology of the US army during the second world war.
The author states that for an organization to nurture innovation, the following conditions should be met:
Phase Separation and Dynamic Equilibrium
Create phase separation and dynamic equilibrium: to separate the artists, who want to create crazy technology, from soldiers whose discipline ensures that the technology is being implemented efficiently (quality, cost, time). And create a continuous exchange of ideas, information, and people between the two groups (dynamic equilibrium) to allow the transfer of technology from the innovation phase to the implementation phase, and to allow the transfer of field experience to innovators.
The Leader as a Gardener
Innovation leaders should be like gardeners: their role is to balance between the two groups and to manage the transfer between them. Not to intervene as soldiers, nor to contribute as artists. And leaders should love their artists and soldiers equally.
Beware the Bandwagon Effect
In theory, there is no difference between theory and practice, but in practice there is.
Yogi Berra
The Ride of a Lifetime – Robert Iger
Title: The Ride of a Lifetime
Author: Robert Iger
Publication Date: 2019
Recommendation Score: 4.5/5
Robert Iger had been the CEO of the Walt Disney Company for 15 years. In his book “The Ride of a Lifetime”, Iger tells his story from humble beginnings to global fame. In hindsight, the author tries to extract some lessons for successful leadership. The book is pleasant to read. Its storytelling is enjoyable. It gives you insights into how the life of a CEO looks like.
I recommend it: enjoy the story and take the lessons with a grain of salt.
Book Review
Leadership is not an exact science, and most books dealing with it are a waste of time. The best thing about “The Ride of a Lifetime” is the no-nonsense approach to leadership; the author tells you what has worked for him and what has not. There are no references to (HBS) academic theories, nor pseudo-scientific studies. When I finished reading the book, the impression I had was that leadership is all about being trustworthy, emotionally aware, and able to take bold risks.
The author starts the first chapter by “This book is not a memoir”, as he wants it to be a book of lessons. I disagree. Iger is trying to connect the dots backward and to make sense of past events. This process is very risky, especially when based on one person’s perspective. It is prone to the hindsight bias; when we try to find causality between correlated events where there might be none. The author admits the role of chance at the end of the book, but convey the message that the traits that served him well are the reason for his achievements. This is why I think that the lessons should be taken with a grain of salt. Some problems have no unique solution. Again, leadership is not an exact science.
Continue reading “The Ride of a Lifetime – Robert Iger”
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